DESCRIPTION (Taken directly from applicant's abstract); The fundamental strength of the zebrafish genetic system is phenotypic analysis. Embryos are accessible and optically clear, enabling defects that result from mutation to be readily scored. Thus, from the start, any large-scale genomic effort should exploit this unique property of a vertebrate genetic system. The overall goal of this proposal is to assemble a panel of deletions that uncovers the zebrafish genome. The deletion mapping panel will be a shared resource to assist zebrafish researchers in the identification of genes responsible for existing mutations, fulfilling the centraL objective of the Genomic Resources of the Zebrafish RFA. Previously identified and newly-induced gamma-ray mutagenized strains will be collected. Deficiency mutant phenotypes will be catalogued in an on- line database and mutations preserved as frozen sperm for later retrieval. Genomic DNA prepared from haploid mutants pre-selected for chromosomal deficiencies will be arrayed in multi-well plates for high-throughput PCR mapping of markers, cloned genes and ESTs, and for ease of distribution to the community. Cytological tools will also be developed to facilitate characterization of chromosomal rearrangements. As in non-vertebrate genetic systems, a zebrafish deletion panel is an essential resource, providing the necessary bridge between DNA sequence and gene function.